A major Australian coal seam gas miner on Sunday said it had discovered traces of carcinogenic chemicals at a number of its monitoring sites, fuelling debate about the contentious industry.
Arrow Energy, which has interests across some 65,000 square kilometres of Australia's coal-rich east, said it found "minute traces" of highly toxic benzene, toluene and xylene in five of its 14 test bores.
Taken over three days at Arrow's Queensland operations as part of routine six-monthly testing, the samples showed low readings of the so-called BTEX chemicals, which can harm the central nervous system and cause cancer.
"The water in this aquifer, where the shallow bores are drilled, is not suitable for drinking water, nor to water stock or irrigate crops," Arrow said.
"Further testing is planned, with the Department of Environment and Resource Management, to confirm the results... Arrow has notified the relevant landholders."
There is a growing community backlash to the booming coal seam gas (CSG) industry in Australia, where farmers and environmentalists are questioning its safety and fear vital underground water sources are at risk.
CSG miners typically extract the naturally-occurring gases from coal seams by injecting chemicals and water into rock at extremely high pressure, a controversial process known as hydraulic fracturing, or "fracking".
Arrow said it did not use fracking in its Queensland operations and was examining whether the chemicals were "naturally occurring or introduced through grease used in the bore drilling process".
"There is no connection between this process and CSG production activities," it said.
Mining tycoon Clive Palmer spoke out against CSG Saturday, claiming offshore operators had questioned whether Australians were skilled or well trained enough to do the work safely.
The thermal coal miner said CSG extraction, currently being investigated by a government committee, carried the real risk of water table contamination which could impact livestock and human health.
Drew Hutton, founder of the anti-CSG group Lock the Gate, said BTEX chemicals were very toxic and some of the traces found in the Arrow bores were at levels as high as 16 parts per billion.
"The regulatory authorities usually prescribe one part per billion as the maximum allowable content," Hutton told ABC Radio.
Arrow estimates it has at least 70,000 petajoules of gas in its fields, the equivalent of more than 12 billion barrels of oil, which is intended for sale in Australia and to export overseas, as the world seeks cleaner energy sources.
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